I don't wash before I sew. I have a had a couple of surprises where I got some bleeding, but no one knew but me. I have never had one part of a quilt shrink more than another after the piecing and quilting has been done. It seems to me that the cutting into smaller sections, spreading the pieces around, and then stabilizing them by quilting them, keep the shrinkage more spread out and not visible. Of course, any of you who have read my posts, know I am a lazy quilter. Washing would cause me so much more work. I don't like starching and pressing to begin with and can't image having to do a bunch of fabric at one time. Color Catchers are one of the best things that have ever been invented.